As a participating institution in the Primary Breast Cancer Therapy Group (NSABP), we will contribute to ongoing protocols, as well as follow up on patients already entered and obtain tissues and sera for biological markers. The present application seeks funding: (a) to permit continued patient accrual in ongoing protocols, (b) to continue follow-up of patient entered into protocols, (c) to collect appropriate biological material. The protocols are: 1) B-06 which is a trial to compare the worth of segmental mastectomy with and without breast radiation with total mastectomy plus axillary dissection. All patients will undergo axillary dissection and those with histologically positive lymph nodes will receive adjuvant chemotherapy. 2) B-09 which is a trial to determine whether the anti-estrogen Tamoxifen, when combined with chemotherapy, improves the results obtained with adjuvant chemotherapy alone. 3) B-07 and B-08 are closed for patient entry, but patients entered will be followed. Finally, an aim of this proposal is to enhance the multidisciplinary approach of this institute in clinical trials.